Put sifted flours into a small mixing bowl. Add egg and salt and pour in water gradually to make a smooth and runny batter. Strain the batter to remove any lumps. Leave aside to stand for 30 minutes.
Heat oil in a deep saucepan. Heat the pie tee mould in the hot oil for 1-2 minutes. Remove the hot pie tee mould and dip into the batter.
Then dip the mould back into the hot oil and keep it there until pie tee is golden brown. Loosen the pie tee gradually until it slips away from the mould.
Remove the pie tee cases and drain well on absorbent paper towels. When cool, store in an airtight container to retain crispiness.
Heat oil in a wok and fry garlic, shallot and dried prawns until fragrant. Add yam beans, carrot and seasoning. Stir and cook, tossing the vegetables well until almost dry. Dish up and cool completely.
Serve pie tee shells with the filling topped with a little chilli sauce and some chopped spring onion.